The present invention relates to a method and apparatus for measuring the length of a waste log and/or for measuring the weight of the waste log while compacting and transferring the waste log for transport.
Waste compaction devices are generally known. Such devices are commonly used at waste transfer stations to receive solid waste material and to compact the solid waste material for transport. Some compaction devices, known as tamping devices, are adapted for use on trailers which transport the waste material to a disposal site (e.g., a land fill, incinerator, and the like). Initially, loose waste material is loaded onto the trailer, and then the tamping device is used to compact the loose waste material while it is already on the trailer. Such tamping devices, however, require the trailer to be present during the entire compaction operation. Also, because the trailer tamping device presses the waste material against the trailer""s walls and/or floor, the trailer is subjected to very strong forces and must be reinforced to reduce the likelihood of failure. Such forces nevertheless tend to reduce the useful life of the trailer, when compared to trailers that receive and transport the waste material after compaction only.
In order to avoid the problems associated with tamping devices, efforts have been made to provide compaction devices which perform the compaction process internally and transfer the compacted waste material in log form to the trailer. Such compaction devices generally avoid the problem of exposing the trailer to the compaction forces.
A primary object of compaction devices is to optimize the density of the waste log (i.e., optimize the amount of waste material per unit volume of the waste log). Some conventional compaction devices therefore contain a powerful hydraulic ram which moves through a cylinder to compress the waste material. In particular, the waste material is loaded into the cylinder, and the ram is actuated to compress the waste material and reduce or eliminate voids therein. After compression, the waste material is pushed onto the trailer for transportation to the disposal site. Conventional compaction devices, however, lack any reliable way of automatically determining the length of the waste log and/or weight of the waste log.
Since trailers have limited dimensions, it is desirable to provide a way of automatically determining when the compressed waste log has reached a predetermined maximum length which a particular trailer can accommodate. If the length cannot be readily determined and the waste log ends up being too long, it may become jammed in the trailer, making unloading difficult, time consuming, and expensive. If the waste log is shorter than what the trailer can accommodate, then the trailer""s capacity is not being used to its fullest extent. In this regard, the trailer is not being used as efficiently as possible. The waste material left behind eventually must be transported to the disposal site, thus requiring additional trips to the disposal site. This results in unnecessary expenditures of fuel, unnecessary wear-and-tear on the trailers and the tractors which pull them, as well as increased labor costs (drivers, mechanics, and the like). There is consequently a need in the art for a way of automatically determining when the compressed waste log has reached the predetermined maximum length so that the waste log can be cut-off automatically at that length and transported efficiently to the disposal site.
Trailers also have weight restrictions which are imposed by the trailer manufacturer, by law, and/or by a transportation authority (e.g., state departments of transportation or a federal agency). If the waste log becomes too heavy, unloading of some of the compacted waste may become necessary in order to comply with the weight restrictions of the trailer or to avoid a dangerous situation. Unloading of the excess compacted waste, however, is generally time-consuming and highly impractical. Similarly, if the waste log is lighter than what the trailer can accommodate, then the trailer""s capacity is not being used to its fullest extent. The waste material left behind eventually must be transported to the disposal site, thus requiring additional trips to the disposal site. This also results in unnecessary expenditures of fuel, unnecessary wear-and-tear on the trailers and the tractors which pull them, as well as increased labor costs. There is consequently a need in the art for a way of automatically determining when the compressed waste log has reached a predetermined maximum weight, to permit termination of the flow of waste material into the waste log and transfer of the waste log onto the trailer.
A primary object of the present invention is to satisfy the aforementioned needs in the art by providing a method and apparatus for measuring the length of a waste log and/or for measuring the weight of the waste log while compacting and transferring the waste log for transport.
To achieve this and other objects, the present invention provides a compaction and transfer apparatus adapted to measure the length of a waste log during compaction and transfer thereof. The apparatus comprises a compaction chamber, a closure device, a compaction ram, and a movement detector. The compaction chamber is adapted to receive waste material. The compaction chamber has a discharge opening. The closure device is selectively movable into and out of the discharge opening to control the size of the discharge opening. The compaction ram is movable through the chamber to press the waste material against the closure device and thereby provide compaction of the waste material. The movement detector preferably is mounted on the closure device. The movement detector is adapted to detect movement of the waste material through the discharge opening, which movement corresponds to the length of the waste log extending out of the discharge opening.
Also provided by the present invention is a method of measuring the length of a waste log during a compaction and transfer operation. The method comprising the steps of: providing a compaction chamber to accommodate waste material; loading waste material into the compaction chamber; compacting the waste material to form the waste log; opening a discharge opening of the compaction chamber, at least partially, to permit transfer of the waste log out of the compaction chamber; and detecting movement of the waste log through the discharge opening. The movement corresponds to the length of the waste log extending out of the compaction chamber.
The present invention also provides a compaction and transfer apparatus adapted to measure the weight of a waste log during compaction and transfer thereof. The apparatus comprises a compaction chamber, a closure device, a compaction ram, and a weight detector.
The compaction chamber is adapted to receive waste material. The compaction chamber has a discharge opening. The closure device is selectively movable into and out of the discharge opening to control the size of the discharge opening. The compaction ram is movable through the chamber to press the waste material against the closure device and thereby provide compaction of the waste material. The weight detector is adapted to detect a total weight of the waste material in the compaction chamber and any portion of the waste log which extends out through the discharge opening.
Also provided by the present invention is a method of measuring the weight of a waste log during a compaction and transfer operation. The method comprises the steps of: providing a compaction chamber to accommodate waste material; loading waste material into the compaction chamber; detecting an initial weight of the waste material; compacting the waste material to provide a waste log; retracting the compaction ram; loading additional waste material into the compaction chamber; and detecting any incremental increases in the weight of the waste material attributable to the additional waste material and keeping a running total of the initial weight and the incremental increases, the running total corresponding to the weight of the waste log; compacting the waste material and the additional waste material to augment the waste log; and opening, at least partially, a discharge opening of the compaction chamber to permit transfer of the waste log out of the compaction chamber.
The term xe2x80x9cwastexe2x80x9d is to be broadly construed. It encompasses more than materials which cannot be reused. The term xe2x80x9cwastexe2x80x9d, for example, encompasses materials which are to be transported to, and processed by, a recycling facility.
The above and other objects and advantages will become more readily apparent when reference is made to the following description taken in conjunction with the accompanying drawings.